Build-it-yourself ‘ghost guns’ bypass California’s...

1of5A police officer walks near one of the crime scenes after a shooting rampage in Rancho Tehama Reserve (Tehama County) that killed five people last week.Photo: ELIJAH NOUVELAGE, AFP/Getty Images

2of5In this Aug. 29, 2017, photo, an ATF agent poses with homemade rifles, or "ghost guns," at an ATF field office in Glendale, Calif. Police say Kevin Neal, who was barred from having guns because of a restraining order, made the two high-powered rifles he used in his shooting rampage in Northern California on Tuesday, Nov. 14. (AP Photo/Jae C. Hong)Photo: Jae C. Hong, Associated Press

3of5One of the bullets pierced an exterior wall at the Rancho Tehama Elementary School during Kevin Janson Neal’s shooting rampage at Rancho Tehama Reserve in Tehama County on Tuesday.Photo: Rich Pedroncelli, Associated Press

4of5FBI investigators check out the elementary school in the small community of Rancho Tehama Reserve in Tehama County, where a gunman went on a shooting spree on Tuesday.Photo: Michael Macor, The Chronicle

5of5

The man who shot five people to death on a rampage through a small town in the northern Central Valley couldn’t buy guns legally. But by building his own untraceable weapons, he was able to amass an illegal arsenal.

Kevin Janson Neal used at least two homebuilt semiautomatic rifles to massacre his wife and four other residents of Rancho Tehama Reserve in Tehama County, authorities who seized the weapons said.

Such “ghost guns” are slipping through a loophole in California’s tough firearms laws, according to gun control proponents. One manufacturer of the technology that makes such weapons easy to build says the state’s tough-on-guns stance has created a demand for workarounds that is making him rich.

Anyone buying a gun in California must undergo a background check, and semiautomatic rifles are highly regulated under the state’s assault weapons ban. But state law does not regulate firearms kits and individual parts as strictly. So with only rudimentary mechanical skills and a few tools, amateur gunsmiths can build their own firearms — and get away with not registering them and leaving off serial numbers that would make them traceable.

“Homemade firearms are going to be a bigger problem in the future as the popularity of these do-it-yourself kits increases,” said Ari Freilich, an attorney with the Giffords Law Center to Prevent Gun Violence in San Francisco. “Criminals that would not pass a background check are attracted to this source of weaponry.”

Opponents of gun control counter that it’s California gun laws themselves — among the strictest in the nation — that are producing more do-it-yourself gunsmiths like Neal and spreading ghost guns around the state.

Neal, 43, was shot to death by sheriff’s deputies Tuesday after terrorizing the unincorporated town of 1,500 for nearly half an hour. Authorities say that in addition to the people he killed, Neal wounded nine others before he was taken down. He fired into an elementary school building, and only quick-thinking staffers who locked down classrooms as they heard the approaching gunfire kept Neal from slaughtering schoolchildren, authorities said.

When they searched his rundown home on a dirt road called Bobcat Lane, sheriff’s deputies found the body of Neal’s wife stuffed beneath the floorboards. They suspect Neal killed her the day before his rampage.

During his killing spree, Neal used two semiautomatic rifles that had been built “in an illegal manner,” said Assistant Sheriff Phil Johnston.

He did not say when authorities believe Neal assembled the rifles or what made them illegal. But Neal was barred from having any firearms because of a criminal protective order and separate restraining order that had been imposed on him after he allegedly attacked his neighbors in January.

Rifles with detachable magazines, and fixed magazines with a capacity of more than 10 rounds, are illegal in California. During the January incident, Neal stabbed and beat two neighbors he held at gunpoint with an illegal Bushmaster AR-15 assault rifle, Tehama County prosecutors said. He was charged with several crimes, including assault with a deadly weapon and possession of an assault weapon, and was out on $160,000 bail when he shot up the town Tuesday.

A booking photo provided by the Tehama County Sheriff of Kevin Janson Neal, 43 who went on a shooting spree yesterday morning killing five people and wounding ten yesterday morning.

Photo: Michael Macor, The Chronicle

Before the January episode, Neal had no criminal convictions and was not restricted from buying firearms, District Attorney Gregg Cohen said. Neal had relinquished one of his handguns to authorities on Feb. 22 after his neighbors obtained a restraining order against him, court papers show.

That restraining order would have shown up in background checks required under state law for gun purchasers, barring Neal from being able to buy firearms legally. However, any guns he built himself — before or after the restraining order was issued — wouldn’t have been known to law enforcement.

The front yard at Neal’s home was littered with various tools and several decaying cars he had been working on. He apparently had the mechanical know-how and tools to build guns as well.

“You can get parts through a variety of sources,” Johnston said, adding that “the more restrictive the laws” are on guns, the more “criminal elements build their own.”

At the heart of do-it-yourself kits is the gun’s lower receiver, or frame — the part that the federal government defines as a “firearm.”

Other gun parts don’t have serial numbers and can be bought and sold freely. But the receiver — a small piece that the handle, trigger, barrel and other parts connect to — is treated as a complete gun and is subject to state and federal regulations such as background checks for buyers.

To get around such laws, companies have created workarounds, including selling partially completed receivers — known as “80 percent” receivers — that are not legally defined as firearms. They require only that a do-it-yourself gunmaker make a few cutouts and drill a couple of holes to assemble a working weapon.

Once the buyer finishes the receiver, other parts can be added, turning it into an untraceable firearm with no serial number. Lower receivers can also be made in a 3-D printer or machined with increasingly low-cost countertop mills, among other emerging technologies.

One such machine is sold by Defense Distributed of Austin, Texas, under the name Ghost Gunner 2. It mills lower receivers out of hunks of aluminum and is sold online for $1,675.

Another company, American Weapons Components in Oceanside (San Diego County), sells more than 75,000 do-it-yourself kits online every year, said David Fry, president of Giffords Law Center to Prevent Gun Violence. Company representatives did not return phone calls or emails seeking comment.

Some companies that sell gun kits host build parties where experienced hands show first-timers how to put together the parts and tweak the partially built receivers.

Gun-control proponents in California say the Tehama County massacre shows that inventive gun-part merchants are steps ahead of legislators in circumventing state gun laws, and that regulations need to be shored up.

Freilich wants such gun assembly kits “to be sold and treated as firearms” and be made subject to state gun laws. “It’s time to revisit the policy and see if we can make progress on it,” he said.

But some efforts to restrict homemade guns have failed in California. Last year, Gov. Jerry Brown vetoed AB1673, a bill supported by Freilich’s group that would have extended the definition of “firearm” to included unfinished frames or receivers.

In his veto message, Brown said the wording of the bill was “unduly vague” and could have “far-reaching and unintended consequences.”

In September 2014, Brown vetoed a bill that would have required all gun parts to have serial numbers and their buyers to go through background checks.

That isn’t to say Brown has a laissez-faire policy on guns. Even as he vetoed AB1673, the governor signed six gun-control bills, including one requiring background checks for ammunition purchasers.

Brown later signed AB857, requiring anyone who builds a homemade firearm to apply for a serial number with the state Justice Department and affix it to the weapon. The law takes effect July 1, 2018.

Californians are some of the most savvy gun owners in the country, and many pride themselves on their detailed knowledge of the laws, Wilson said.

“It’s like people in California enjoy when they pass a ban because they have an enthusiasm for making a contraption to work around the law,” he said. “I don’t think that’s noble. I wish people ignored gun laws completely.”

Evan Sernoffsky is a reporter for the San Francisco Chronicle specializing in criminal justice, crime and breaking news. He’s covered some of the biggest Bay Area news stories in recent memory, including wildfires, mass shootings and criminal justice reform efforts in San Francisco. He has given a voice to victims in some of the region’s biggest tragedies, carefully putting himself in challenging situations to make sure their stories are told. He works out of San Francisco’s Hall of Justice where he keeps watch on the city’s courts and hits the streets to expose the darker side of a city undergoing rapid change. He moved to the Bay Area from Oregon where he grew up and worked as a journalist for several years.